Make CFX_WideString(const CFX_WideString&) explicit.

xfa/fxfa/include/fxfa.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef XFA_FXFA_INCLUDE_FXFA_H_
 #define XFA_FXFA_INCLUDE_FXFA_H_
 
 #include <vector>
@@ skipping 396 matching lines @@
                                      CFX_Matrix* pMatrix,
                                      const CFX_RectF& rtUI) {
     return FALSE;
   }
   virtual int32_t CountPages(CXFA_FFDoc* hDoc) = 0;
   virtual int32_t GetCurrentPage(CXFA_FFDoc* hDoc) = 0;
   virtual void SetCurrentPage(CXFA_FFDoc* hDoc, int32_t iCurPage) = 0;
   virtual FX_BOOL IsCalculationsEnabled(CXFA_FFDoc* hDoc) = 0;
   virtual void SetCalculationsEnabled(CXFA_FFDoc* hDoc, FX_BOOL bEnabled) = 0;
   virtual void GetTitle(CXFA_FFDoc* hDoc, CFX_WideString& wsTitle) = 0;
-  virtual void SetTitle(CXFA_FFDoc* hDoc, const CFX_WideStringC& wsTitle) = 0;
+  virtual void SetTitle(CXFA_FFDoc* hDoc, const CFX_WideString& wsTitle) = 0;
   virtual void ExportData(CXFA_FFDoc* hDoc,
                           const CFX_WideStringC& wsFilePath,
                           FX_BOOL bXDP = TRUE) = 0;
   virtual void ImportData(CXFA_FFDoc* hDoc,
                           const CFX_WideStringC& wsFilePath) = 0;
   virtual void GotoURL(CXFA_FFDoc* hDoc,
                        const CFX_WideStringC& bsURL,
                        FX_BOOL bAppend = TRUE) = 0;
   virtual FX_BOOL IsValidationsEnabled(CXFA_FFDoc* hDoc) = 0;
   virtual void SetValidationsEnabled(CXFA_FFDoc* hDoc, FX_BOOL bEnabled) = 0;
@@ skipping 111 matching lines @@
   virtual void Release() = 0;
   virtual void Reset() = 0;
   virtual CXFA_FFWidget* MoveToFirst() = 0;
   virtual CXFA_FFWidget* MoveToLast() = 0;
   virtual CXFA_FFWidget* MoveToNext() = 0;
   virtual CXFA_FFWidget* MoveToPrevious() = 0;
   virtual CXFA_FFWidget* GetCurrentWidget() = 0;
   virtual FX_BOOL SetCurrentWidget(CXFA_FFWidget* hWidget) = 0;
 
  protected:
-  ~IXFA_WidgetIterator() {}
+  virtual ~IXFA_WidgetIterator() {}
 };
 
 #endif  // XFA_FXFA_INCLUDE_FXFA_H_